Max Verstappen struggled with his car in FP1 as Red Bull Team Principal Christian Horner admitted they experimented with the Dutchman’s setup.
The two-time champion took to team radio to share his displeasure multiple times throughout the session, which he finished in sixth place.
Verstappen is yet to finish off the podium so far this year, having taken 119 points from a possible 138 in the opening five races.
Speaking about the changes, Horner told Sky Germany: “We tried something that Max didn't like that much. We'll change something during the break and see that we can adjust the car better for him.
“We had to change something in the tuning and are now trying to adjust the car to the track."
READ MORE: Hamilton and Verstappen FORCE each other off the road during Monaco practice
TV coverage showed Max getting increasingly agitated as the session progressed, with multiple outbursts over his radio.
“Yeah the car [in] high speed places is unbelievably difficult to drive.
“It’s the rear bottoming out massively.”
Even towards the end of the session, Verstappen continued to struggle with his car despite further changes to his setup, which resulted in him calling a premature end to his session.
“Ah mate, I want to box, I’m going to shunt like this with the car setup like this.”
With just two more sessions left before Saturday's crucial qualifying, Red Bull will be hoping that any changes they make are effective enough to keep them at the front.
READ MORE: Ted Kravitz: The Notebook star who made Max Verstappen mad